Analysis of the diversity of murine antibodies to dextran B1355. II. Demonstration of multiple idiotypes with variable expression in several strains.

We have developed radioimmunoassays that detect idiotypic (variable region) differences among the alpha(1 leads to 3) dextran-binding meyloma proteins U102, J558, and M104 as well as an assay that detects variable region determinants common to all three proteins. Using these assays, we have examined 7S and 19S anti-alpha(1 leads to 3) dextran antibodies induced in five murine strains of the a1 IgCH linkage group and the recombinant strain BAB/14. All idiotypes were expressed in both 19S and 7S antibodies from all strains, but with considerable strain-specific variability in penetrance. In two strains, one additional type of antibody, which lacked all four idiotypic determinants, generally constituted the bulk of total anti-alpha(1 leads to 3) dextran antibodies.